package org.jeecg.weixin.common.util;

import com.google.common.collect.Lists;
import org.jeecg.weixin.common.annotation.Required;
import org.jeecg.weixin.common.error.WxError;
import org.jeecg.weixin.common.error.WxErrorException;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

/**
 * <pre>
 * bean操作的一些工具类
 * Created by Binary Wang on 2016-10-21.
 * </pre>
 *
 * @author <a href="https://github.com/binarywang">binarywang(Binary Wang)</a>
 */
public class BeanUtils {
	private static Logger log = LoggerFactory.getLogger(BeanUtils.class);

	/**
	 * 检查bean里标记为@Required的field是否为空，为空则抛异常
	 *
	 * @param bean
	 *            要检查的bean对象
	 */
	public static void checkRequiredFields(Object bean) throws WxErrorException {
		List<String> requiredFields = Lists.newArrayList();

		List<Field> fields = new ArrayList<>(Arrays.asList(bean.getClass().getDeclaredFields()));
		fields.addAll(Arrays.asList(bean.getClass().getSuperclass().getDeclaredFields()));
		for (Field field : fields) {
			try {
				boolean isAccessible = field.isAccessible();
				field.setAccessible(true);
				if (field.isAnnotationPresent(Required.class)) {
					// 两种情况，一种是值为null，
					// 另外一种情况是类型为字符串，但是字符串内容为空的，都认为是没有提供值
					boolean isRequiredMissing = field.get(bean) == null
							|| (field.get(bean) instanceof String && StringUtils.isBlank(field.get(bean).toString()));
					if (isRequiredMissing) {
						requiredFields.add(field.getName());
					}
				}
				field.setAccessible(isAccessible);
			} catch (SecurityException | IllegalArgumentException | IllegalAccessException e) {
				log.error(e.getMessage(), e);
			}
		}

		if (!requiredFields.isEmpty()) {
			String msg = String.format("必填字段【%s】必须提供值！", requiredFields);
			log.debug(msg);
			throw new WxErrorException(msg);
		}
	}

}
